SSEP changes Flashcards
What do PTN SSEPs monitor
Monitors general state of cauda equine, important for multi-root manipulations (caudal equina retraction) and potential ischemic events
What do upper and lower leg EMG (free-run and triggered) monitor
Monitors nerve root irritation, important for nerve root manipulations and pedicle screw stimulation
What do MN SSEPs monitor
Monitors general brachial plexus function and cervical spinal cord. Important for assessing cortical changes due to anesthetic and physiologic effects and for detection of a malpositioned patient
Critical event - Laminectomy (Posterior)
Potential for compressive forces on nerve roots as well as dural laceration/tearing
Critical event - Disketomy (Posterior)
Instruments or large disk piece may bump or stretch nerve roots. May involve retraction of nerve roots
Critical event - Interbody cage or graft placement (Posterior)
Requires retraction of the cauda equina causing stretching and compression of multiple nerve roots
Critical event - Pedical screw placement (Posterior)
Breach of pedicle wall can injure or irritate nerve roots
Critical event - Illiac Vessel Retraction (Anterior)
Manipulation and retraction of the large feels supplying lower extremity can cause leg ischemia via surgical occlusion or thrombosis
Critical event - Disketctomy (Anterior)
Potential for compression of the cauda equina or exiting nerve roots, or dural tearing
Critical event - Interbody Cage Placement (Anterior)
Potential for stretching or compression of the cauda equina
Critical event - Vertebral Body Screw Placement (Anterior)
A misplaced vertebral screw can injure nerve roots
Foot drop
Gait abnormality in which the foot “drops” during stepping due to inability or difficulty in dorsiflexing the foot (loss of motor function)
What type of changes are seen in ALIFs
Leg ischemic changes
